Method for preparing equal weight slices of product



1963 5.1-. HENSGEN ETAL 3,105,533

' METHOD FOR PREPARING EQUAL WEIGHT SLICES 0F PRODUCT Original Filed April 4. 1957 5 Sheets-Sheet l INVENTORS fi-RIARO Z. A iza 564W 0605 A; CZEMEMS 5y fl; k v

Oct. 1, 1963 Original Filed April 4. 1957 METHOD FOR PREPARING EQUAL WEIGHT SLICES 0F PRODUCT Sheets-Sheet 2 QM I I I I I I I I I I I I I L 060! A; (Laws/vs "A 71am er Oct. 1, 1963 Original Filed April 4. 1957 B. 1'. HENSGEN ETAL 3,105,533

METHOD FOR PREPARING EQUAL WEIGHT SLICES OF PRODUCT 3 Sheets-Sheet 3 INVENTORS Et'R/VARD 7. Ill-(560V OGDEN A. 625M514? BY %W@ United States Patent Office Patented Get. 1, 19'

"I 65%,652. 11, 19%9, Ser- No.

4 Clmirns. (Cl. 146241) The present invention relates to a method and apparatus for preparing substantially equal weight groups of one or more slices of food products such as meat.

One of the important problems in the meat industry is the producing of packages of product of a predetermined weight. While to one not familiar with the industry it might appear that attempting to maintain a tolerance of half an ounce or so on a pound would not be dilhcult or expensive, there are important problems in costs involved in even the maintaining of a tolerance of this small amount. In the first place, the tolerance must be on the high side, that is, it cannot be plus or minus, because it is generally believed that if a package is indicated as being a pound in weight it must weight at least that. Therefore, to the extent that a tolerance is employed it means that the meat packer is giving away product. When viewed in the light of the enormous number of pounds sold by a meat packer every year, this becomes a very important factor. For example, if a packer sells a million pounds of sliced bacon a year (in the year 1956 the total output of sliced bacon by packers subject to meat inspection by the Federal Government was in excess of one billion pounds), and if he averages a give-away of /4 ounce on every pound he sells, he is giving away 15,625 pounds of bacon a year. If the bacon were selling for 50 a pound, this would be $7,812.53. Put another way, the packer is giving away approximately l /2% as much meat as he sells. This is a greater percentage than thepercentage of net profit that many packers generally make on each dollar of sales. The foregoing illustrates the desirability of re ucing to an absolute minimum the difierence in weight between the weight specified on a package, such as a package of bacon, and the weight of the meat actually contained within that package.

The present solution followed by most meat packers is to have employes weigh groups of slices of bacon and add or subtract slices or portions thereof to endeavor to produce about a pound of bacon. This procedure has numerous disadvantages. In the first place, hand labor is expensive. Secondly, even with a substantial amount of supervision the employes will get careless and thereby give away an excessive amount of product or get the packer into trouble by producing underweight packages. The use of partial slices is not received with favor by the customer. Of course, with other meat products where there is only one slice to a package the expedient of using partial slices becomes impossible.

Various proposals have been suggested in the past for solving this problem. For example, one proposal has been to measure the thickness of a slab of bacon and vary the thickness of the slice in accordance with the thickness of the slab. direction, it has not proven to be a solution of the entire problem.

The principal object of the present invention is to provide a method and apparatus for producing slices of a constant volume, thereby achieving slices of substantially constant weight. With such a procedure the group of slices, whether it be only one slice or a substantial number, will always weigh substantially the same.

In accordance with the method of the present inven- While this may be a step in the right tion measurements of the cross-sectional size of the slab from which the slices are to be cut are made immediately adjacent the cutting knife. To correct for variations in the cross-section dimensions, where the slab or block from which the slices are to be cut has a lengthy side or sides, measurements are made at spaced points along that lengthy side or sides and such measurements are averaged out before the multiplication is made with the measurement or measurements of the other dimension. After the cross-sectional area is determined, the rate of speed with which the block of meat moves with respect to the knife (or vice versa) is adjusted in accordance with the determined cross-sectional area so that the thickness of the slice to be cut is adjusted to obtain a constant volume.

A specific embodiment of the invention is illustrated in the drawings in which:

FIGURE 1 is a diagrammatic representation of an apparatus that will perform the outlined method;

FIGURE 2 is a side view of a structure for measuring a dimension of the block and for converting that measure ment into an electrical signal;

FIGURE 3 is a schematic wiring diagram illustrating the multiplication of the measurements in order to determine the cross-sectional area; and

FIGURE 4 is a schematic illustration of an alternative form of measurement and control apparatus.

Slicing machines are so well-known in the art, for example, see Patents Nos. 2,744,553 and 2,691,398, that the machine has been illustrated only diagrammatically in FIGURE 1. Essentially such a machine comprises a power driven rotary knife generally ill and a conveyor generally 11 for moving the block of product I2 to the knife It). Usually the speed of rotation of knife It is maintained constant so that the rate at which the block 12 is moved towards the knife determines the thickness of the slices cut by each rotation of the knife. Obviously, moving the knife 10 with respect to the block 12 would be the full equivalent of the described structure.

Many well-known forms of conveyor 11 might be employed. For the purpose of illustration the conveyor 11 comprises a belt 13 mounted on sprockets 14. A shaft 15 supporting one of the groups of sprockets 14 is driven from a motor 16 through a sprocket 17 on the output shaft of motor 16, a chain 18, and a sprocket 19 attached to shaft 15.

In the illustrated embodiment motor 16 is a hydraulic motor, as for example a motor produced by Denison Engineering Co. and identified as model TMB-llB. Hydraulic fluid to operate the motor is provided by a hydraulic pump unit generally 23. The hydraulic fluid under pressure from the pump is fed through a pipe 24 to motor 16 and a pipe 2-6 to a control valve 25. After passing through control valve 25 the hydraulic fluid returns through a pipe 27 to a reservoir which is a part of hydraulic pump unit 23. Motor 16 rotates in a direction to move block 12 in the direction indicated by arrow 28.

In the illustrated embodiment the block 12 represents a slab of bacon wherein there is a substantial width to the block with a relatively narrow thickness. Because that thickness will vary over the width of the block, a plurality of thickness-measuring units are employed. In the illustrated embodiment three thickness-measuring units, generally 31, 32. and 33, are employed. Inasmuch as the depth of the block I2 is rather small, only one widthsensing unit generally 34 is employed. Width-sensing unit 34 measures the width of the slab between a fence 35 against which the side of the block 12 opposite the widthsensing unit 34 is pressed. The sensing units 31-33 measure the thickness between the top or" belt 13 and the sensing units.

Referring to FIGURE 2, the structure of the sensing unit 31 is illustrated. The structure of the other sensing units corresponds thereto. Sensing unit 31 comprises a roll 38 that rides on the upper surface of block 12. Roll 38 is rotatably mounted on one portion 39 of an L-shaped member, the other portion 44) of which is mounted for vertical movement in .a bearing 41. A pin 42 projects rom the upper end of portion 45 and is received in a slot 43 in a member 44 pivotally mounted on a pin 45. Both pint 45 and bearing 41 are fixedly attached to the frame (not shown) of the machine. The end of member 44 opposite slot 43 carries a gear segment 46 which engage a gear 47 on the operating shaft 48 of a rotary potentiometer A spring 55 attached to member 44 and to a pin 51 urges member 44 in a clockwise direction about mounting pin 45 and holds sensing roll 38 in contact with the upper surface of the block 12.

The measurements of thickness determined by units 31, 32 and 33 are fed to an averaging unit 55 and the average thickness is then fed to a multiplying unit 56 to which is also fed the information as to the width of the block 12 p as determined by width measuring unit 34. The multiplying unit then produces a signal which corresponds to the cross-sectional area, which information is delivered to a servo-amplifier 57. The servo-amplifier controls the operation of a servo-motor 8 which is connected to and positions valve 25 so as to move the block 12 at a rate of speed to produce slices from the block of a thickness such that the volume of the slice is constant. A feed back potentiometer 59 is coupled to servo-motor 58 to feed a signal back to servo-amplifier 57 to obtain a positioning of valve 25 in accordance with the requirements of the signal fed to, the servo-amplifier by the multiplier 56.

Additional details of the electrical components are illustrated in FIGURE As previously mentioned, the thickness determining unit 31 includes a potentiometer 39. Similarly thickness sensing units 32 and 33 include potentiometers 63 and 64, respectively. Width-sensing unit 34 includes a potentiometer 65. A constant voltage, which for the purposes of illustration may be represented by battery 66, is fed to each of the three thickness potentiometers 49, 63 and 64. The slider of each of these potentiometers is connected through a resistor (numbers 67- 69) to the grid of a vacuum tube 73 of averaging amplifier 55. This amplifier has a feed back between the plate of tube 70 and the grid thereof such that the signal at the plate of the tube is an average of the three voltages impressed on the grid thereof.

The signal from the plate of tube 70 is impressed across potentiometer 65 of the width-sensing unit 34. The signal from the sliding contact of potentiometer '65 will be the product of the multiplication of the input signal, i.e., the average of the three voltages of potentiometers 49, 63 and 64, times the position of the slider of potentiometer 65. Since the position of the slider of potentiometer 65 is determined by the Width of the block 12, this product is they average thickness times the width. It will be seen that with such a hook-up the potentiometer 65 not only acts in the function of determining the width of the block 12, but also acts as the multiplying unit 56. Obviously these two functions could be separated and separate units employed for each separate function. This product of the average thickness times the Width is fed to the servo-amplifier 57 which drives the servo-motor 58. Such amplifiers and motors are well-known in the art and detailed description of them is superfluous. An amplifier and motor similar to that described on page 143 of the book Handbook of Industrial Electronic Circuits, Markus & Zeluif, published by McGraw-Hill Book Company in 1948 would be suitable. As previously mentioned, feed back potentiometer 59 is coupled to the shaft 6%) of the servo-motor 58 to feed a signal back to the servo-amplifier 57, which signal correspondsto the angular position of shaft 6% Thus, when shaft 64 is set for the proper angular position corresponding to the signal fed to the servo-amplifier 57, the servomotor 53 is not energized. Otherwise the servo-motor 4 53 is energized to turn shaft 6! in a direction to correct for the signal being fed to the servo-amplifier 57.

in the embodiment of FIGURE 4, the measurements are made by means of differential transformers. The details of such transformers are illustrated and described in US. Patents Nos. 2,568,587, 2,568,588,'and 2,050,629. As in the previous embodiment, three measurements are made of the thickness of the slab of bacon at spaced points across the Width of the slab. For this purpose three differential transformers, generally 80, 81 and 32, are employed. The primary windings 83, =84 and 85 of the three transformers are connected in parallel and connected to a constant voltage alternator 86. Alternator 86 might be either of a mechanical or an electronic construction. The secondaries 87, 83 and 89 are connected in series and connected to the primary 9% of the widthmeasuring differential transformer generally 91. The secondary 92 of transformer i l is connected to a servoamplifier such as amplifier 57.

The variable cores 8- 3, 9 and 95 of transformers 80- 82, respectively, have feelers thereon represented by wheels 96, 97 and 98, respectively, which contact the upper surface of the slab and position the cores 93-95 in a position with respect to the windings of the transformers corresponding to the relative thickness of the slab at the point of contact of the feelers with the slab. Similarly transformer 9.1 has a variable core 99 having a feeler represented by wheel 1% to contact the side of the slab'and measure the wi th of the slab. As the cores of the transformers move farther between the primary and secondary coils, a greater voltage is induced in the secondary. As the core moves out from between the windings a smaller voltage is induced the secondary. The voltages in transformers 86-82 are added so that the total is a figure which corresponds to the sum of the thicknesses at the three points. Theoretically speaking, this amount should be divided by three before multiplying by the width. However, from a practical point of view dividing by three would merely give a new voltage /3 as large as the summation voltage and just more diflicult to work with because of its smaller amount. Practicali in a specific piece of apparatus, the summation voltage is multiplied directly by the width. This is done by introducing the summation voltage into the primary of the width transformer 9i. and moving the core 99 of that transformer corresponding to the width of the slab. The voltage then produced by the secondary of the width transformer 91 is a voltage which corresponds to the primary voltage times the width, or is a voltage which corresponds to the area of the slab. This voltage is then employed to operate the servo 53 in the manner previously described so as to adjust the speed of movement of the slab whereby the cubic volume of a slice cut from the portion of the slab Where measurements were made will be constant.

In the control apparatus illustrated and described there will be some delay in adjusting the speed of movement of the slab. This delay is utilized and the feelers which take the measurement of the cross-sectional area of the slab are positioned at a point rearwardly of the plane at which the cutting occurs, a distance such that by the time the delay in the measurement and control apparatus occurs the portion of the slab that was measured hasnow moved up to the cutting plane. If the delay in the measurement and control apparatus is not sufficient for this purpose, additional delay may be introduced in the manexact details of construction shown and described for obvious modifications will occur to a person skilled in the art.

We claim:

1. The method of producing a slice of food from a block of said food of a predetermined volume, including the steps of aligning the end of said block with a plane along which said slice is to be cut, measuring one side dimension of said block at a plurality of points across a portion of said block, adding said measurements to obtain a figure corresponding to the average of the measurements, measuring the other side dimension of said portion of said block, multiplying said last measurement with said figure to obtain a second figure corresponding to the cross-sectional area at said portion of said block, and cutting a slice from said portion of a thickness which is a function of said second figure.

2. The method of producing a plurality of slices of food from a nonuniform block of sm'd food, including the steps of orienting said block with respect to a predetermined plane along which said slices are to be cut, successively measuring the cross-sectional area of portions of said block out by imaginary planes substantially parallel to 'said predetermined plane by sensing the dimensions and changes therein of two adjacent surfaces of said lock and multiplying the two dimensions, and moving said block towards said predetermined plane at rates of speed which are functions of the cross-sectional areas of said portions while making cuts along said predetermined plane at given intervals whereby slices of substantially constant volume will be cut from said portions.

3. The method of producing a slice of food of a predetermined volume from a block of said food having nonuniform dimensions, including the steps of orienting said block with respect to a predetermined plane along which said slice is to be cut whereby one end of said block will be substantially parallel to said predetermined plane, measuring one side dimension of said block at a purality of points across a portion of said block, said plurality of points lying in an imaginary plane substantially parallel to said predetermined plme, adding said measurements to obtain a figure corresponding to the average of the measurements, measuring the other side dimension of said portion of said block, multiplying said last measurement with said figure to obtain a second figure corresponding to the cross-sectional area at said portion of said block, moving said block toward said predetermined plane at a rate of speed which is a function of said cross-sectional area of said portion while making a cut along said predetermined plane at a point along said block whereby a slice of said predetermined volume will be cut from said portion. 9

4. The method of producing a slice of food from a block of sad food of a predetermined volume, including the steps of aligning the end of said block with a plane along which said slice is to be cut, measuring one side dimension of said block at a portion thereof, measuring another side dimension of said portion of said block, multiplying said last measurement with said first measurement to obtain a figure corresponding to the cross-sectional area at said portion of said block, and cut-ting a slice from said portion of a thickness which is a function of said figure.

References Cited in the file of this patent UNITED STATES PATENTS 1,989,252 Walter Jan. 29, 1935 2,226,527 Vvalter Dec. 24, 1940 2,630,043 Kolisch Mar. 3, 1953 2,708,368 Kolisch May 17, 1955 2,768,666 Garapolo et al. Oct. 30, 1956' 2,815,759 Molins et al Dec. 10, 1957 2,858,614 Schuenemann Nov. 4, 1958 2,861,683 Gilman Nov. 25, 1958 2,954,811 Hensgen et a1 Oct. 4, 1960 3,010,499 Dahms et al Nov. 28, 1961 FOREIGN PATENTS 861,665 Germany Jan. 5, 1953 OTHER REFERENCES Continuous Gaging in Steel Mills Produces Profit, by A. S. Unano, in March 1956 issue of Automation, pages 5257.

Bacon Giveaway on the Way Out, National Provisioncr Magazine, October 20, 1956, pages 32-35. 

4. THE METHOD OF PRODUCING A SLICE OF FOOD FROM A BLOCK OF SAID FOOD OF A PREDETERMINED VOLUME, INCLUDING THE STEPS OF ALIGNING THE END OF SAID BLOCK WITH A PLANE ALONG WHICH SAID SLICE IS TO BE CUT, MEASURING ONE SIDE DIMENSION OF SAID BLOCK AT A PORTION THEREOF, MEASURING ANOTHER SIDE DIMENSION OF SAID PORTION OF SAID BLOCK, MULTIPLYING SAID LAST MEASUREMENT WITH SAID FIRST MEASUREMENT TO OBTAIN A FIGURE CORRESPONDING TO THE CROSS-SECTIONAL AREA AT SAID PORTION OF SAID BLOCK, AND CUTTING A SLICE FROM SAID PORTION OF A THICKNESS WHICH IS A FUNCTION OF SAID FIGURE. 